package com.douyin.service;

import com.douyin.entity.ParseRecord;
import com.douyin.entity.StatisticsDetail;
import com.douyin.entity.ErrorStatistics;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.time.LocalDate;
import java.util.*;
import java.util.stream.Collectors;

@Slf4j
@Service
@RequiredArgsConstructor
public class StatisticsService {
    
    private final ParseRecordService parseRecordService;
    
    /**
     * 获取综合统计报告
     */
    public Map<String, Object> getComprehensiveReport(LocalDateTime startTime, LocalDateTime endTime) {
        Map<String, Object> report = new HashMap<>();
        
        // 基础统计
        Map<String, Object> basicStats = parseRecordService.getDetailedStatistics(startTime, endTime);
        report.put("basicStatistics", basicStats);
        
        // 时间趋势分析
        List<Map<String, Object>> trends = getTimeTrends(startTime, endTime);
        report.put("timeTrends", trends);
        
        // 用户行为分析
        Map<String, Object> userBehavior = getUserBehaviorAnalysis(startTime, endTime);
        report.put("userBehavior", userBehavior);
        
        // 性能分析
        Map<String, Object> performance = parseRecordService.getPerformanceStats(startTime, endTime);
        report.put("performance", performance);
        
        // 错误分析
        List<Map<String, Object>> errorAnalysis = parseRecordService.getTopErrors(startTime, endTime, 10);
        report.put("errorAnalysis", errorAnalysis);
        
        // 地理分析
        Map<String, Object> geoAnalysis = getGeographicalAnalysis(startTime, endTime);
        report.put("geographicalAnalysis", geoAnalysis);
        
        return report;
    }
    
    /**
     * 获取实时监控数据
     */
    public Map<String, Object> getRealtimeMonitoring() {
        Map<String, Object> monitoring = new HashMap<>();
        
        LocalDateTime now = LocalDateTime.now();
        LocalDateTime oneHourAgo = now.minusHours(1);
        LocalDateTime oneDayAgo = now.minusDays(1);
        
        // 最近1小时统计
        Map<String, Object> lastHourStats = parseRecordService.getDetailedStatistics(oneHourAgo, now);
        monitoring.put("lastHour", lastHourStats);
        
        // 最近24小时统计
        Map<String, Object> last24HoursStats = parseRecordService.getDetailedStatistics(oneDayAgo, now);
        monitoring.put("last24Hours", last24HoursStats);
        
        // 系统健康状态
        Map<String, Object> healthStatus = getSystemHealthStatus();
        monitoring.put("systemHealth", healthStatus);
        
        return monitoring;
    }
    
    /**
     * 获取用户行为分析
     */
    public Map<String, Object> getUserBehaviorAnalysis(LocalDateTime startTime, LocalDateTime endTime) {
        Map<String, Object> analysis = new HashMap<>();
        
        // 活跃时段分布
        Map<Integer, Long> hourlyDistribution = getHourlyActivityDistribution(startTime, endTime);
        analysis.put("hourlyActivity", hourlyDistribution);
        
        // 设备偏好分析
        Map<String, Long> devicePreference = getDevicePreferenceStats(startTime, endTime);
        analysis.put("devicePreference", devicePreference);
        
        // 平台偏好分析
        Map<String, Long> platformPreference = getPlatformPreferenceStats(startTime, endTime);
        analysis.put("platformPreference", platformPreference);
        
        // 重试行为分析
        Map<String, Object> retryBehavior = getRetryBehaviorAnalysis(startTime, endTime);
        analysis.put("retryBehavior", retryBehavior);
        
        return analysis;
    }
    
    /**
     * 获取导出数据
     */
    public List<Map<String, Object>> getExportData(LocalDateTime startTime, LocalDateTime endTime, 
                                                  String type, Map<String, Object> filters) {
        List<Map<String, Object>> exportData = new ArrayList<>();
        
        switch (type.toLowerCase()) {
            case "records":
                exportData = getRecordsExportData(startTime, endTime, filters);
                break;
            case "statistics":
                exportData = getStatisticsExportData(startTime, endTime, filters);
                break;
            case "errors":
                exportData = getErrorsExportData(startTime, endTime, filters);
                break;
            case "users":
                exportData = getUsersExportData(startTime, endTime, filters);
                break;
        }
        
        return exportData;
    }
    
    // 私有辅助方法
    
    private List<Map<String, Object>> getTimeTrends(LocalDateTime startTime, LocalDateTime endTime) {
        // 实际实现需要在数据库层面进行时间聚合查询
        List<Map<String, Object>> trends = new ArrayList<>();
        
        // 按小时统计趋势
        LocalDateTime current = startTime != null ? startTime : LocalDateTime.now().minusDays(7);
        LocalDateTime end = endTime != null ? endTime : LocalDateTime.now();
        
        while (current.isBefore(end)) {
            LocalDateTime hourEnd = current.plusHours(1);
            Map<String, Object> hourStats = parseRecordService.getDetailedStatistics(current, hourEnd);
            
            Map<String, Object> trendPoint = new HashMap<>();
            trendPoint.put("timestamp", current);
            trendPoint.put("totalRequests", hourStats.get("totalRequests"));
            trendPoint.put("successRequests", hourStats.get("successRequests"));
            trendPoint.put("failedRequests", hourStats.get("failedRequests"));
            trendPoint.put("successRate", hourStats.get("successRate"));
            
            trends.add(trendPoint);
            current = hourEnd;
        }
        
        return trends;
    }
    
    private Map<String, Object> getSystemHealthStatus() {
        Map<String, Object> health = new HashMap<>();
        
        LocalDateTime now = LocalDateTime.now();
        LocalDateTime fiveMinutesAgo = now.minusMinutes(5);
        
        // 最近5分钟的错误率
        Map<String, Object> recentStats = parseRecordService.getDetailedStatistics(fiveMinutesAgo, now);
        long totalRecent = (Long) recentStats.getOrDefault("totalRequests", 0L);
        long failedRecent = (Long) recentStats.getOrDefault("failedRequests", 0L);
        double recentErrorRate = totalRecent > 0 ? (double) failedRecent / totalRecent : 0.0;
        
        health.put("recentErrorRate", recentErrorRate);
        health.put("status", recentErrorRate < 0.1 ? "healthy" : recentErrorRate < 0.3 ? "warning" : "critical");
        health.put("lastUpdateTime", now);
        
        return health;
    }
    
    private Map<Integer, Long> getHourlyActivityDistribution(LocalDateTime startTime, LocalDateTime endTime) {
        // 这需要在数据库层面实现按小时分组的查询
        Map<Integer, Long> distribution = new HashMap<>();
        for (int i = 0; i < 24; i++) {
            distribution.put(i, 0L);
        }
        return distribution;
    }
    
    private Map<String, Long> getDevicePreferenceStats(LocalDateTime startTime, LocalDateTime endTime) {
        // 这需要在数据库层面实现按设备类型分组的查询
        return new HashMap<>();
    }
    
    private Map<String, Long> getPlatformPreferenceStats(LocalDateTime startTime, LocalDateTime endTime) {
        // 这需要在数据库层面实现按平台分组的查询
        return new HashMap<>();
    }
    
    private Map<String, Object> getRetryBehaviorAnalysis(LocalDateTime startTime, LocalDateTime endTime) {
        // 分析用户重试行为模式
        Map<String, Object> analysis = new HashMap<>();
        analysis.put("avgRetryCount", 0.0);
        analysis.put("maxRetryCount", 0);
        analysis.put("retrySuccessRate", 0.0);
        return analysis;
    }
    
    private Map<String, Object> getGeographicalAnalysis(LocalDateTime startTime, LocalDateTime endTime) {
        Map<String, Object> analysis = new HashMap<>();
        
        // 按国家统计
        Map<String, Long> countryStats = new HashMap<>();
        analysis.put("byCountry", countryStats);
        
        // 按地区统计
        Map<String, Long> regionStats = new HashMap<>();
        analysis.put("byRegion", regionStats);
        
        // 按城市统计
        Map<String, Long> cityStats = new HashMap<>();
        analysis.put("byCity", cityStats);
        
        return analysis;
    }
    
    private List<Map<String, Object>> getRecordsExportData(LocalDateTime startTime, LocalDateTime endTime, 
                                                          Map<String, Object> filters) {
        // 导出解析记录数据
        return new ArrayList<>();
    }
    
    private List<Map<String, Object>> getStatisticsExportData(LocalDateTime startTime, LocalDateTime endTime, 
                                                             Map<String, Object> filters) {
        // 导出统计数据
        return new ArrayList<>();
    }
    
    private List<Map<String, Object>> getErrorsExportData(LocalDateTime startTime, LocalDateTime endTime, 
                                                         Map<String, Object> filters) {
        // 导出错误数据
        return new ArrayList<>();
    }
    
    private List<Map<String, Object>> getUsersExportData(LocalDateTime startTime, LocalDateTime endTime, 
                                                        Map<String, Object> filters) {
        // 导出用户数据
        return new ArrayList<>();
    }
}